Light air prep:
Dump fuel
Dump water
Dump batteries (except one small one)
Dump spares
Dump any padlocks
Have crew empty out their pockets before leaving dock, trim fingernails, take laxatives.

THEN we really start paring dead weight. :-)

In the bicycle world people used to drill holes in their frames and take spokes out of their wheels. I even saw one guy drill holes in his rims. It wasn't until carbon fiber was commonplace that they stopped doing this.
So add to your list:
Drill holes in the mast.
Take off a couple of shrouds.
Get thinner standing rigging.
Drill holes in the deck and freeboard.
Cut off the tiller.
or
Buy a carbon fiber racing sled.
Racing can drive you crazy, but it sure is fun to sail tight and do well.